Gian-Kasper Plattner

Head WGI TSUUniversity of Bern

IPCC 5th Assessment Cycle (2008-2014):

Human influence on the climate system is clear.

Continued GHG emissions will cause further warming and

amplify existing risks.

Changes in climate have caused impacts in natural

and human systems.

Multiple pathways exist to likely

limit warming to below 2°C.

Warming of the climate systemis unequivocal

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Ocean warming dominates the increase in energy stored in the climate system

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Human influence on the climate system is clear, and recent anthropogenic emissions of

greenhouse gases are the highest in history.

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Global surface temperature change for the end of

the 21st century is likely to exceed 1.5°C relative

to 1850−1900 for all scenarios except RCP2.6.

Global mean surface temperature change from 1986-2005

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Further warming will increase the likelihood of

severe, pervasive and irreversible impacts for

people and ecosystems.

Change in average surface temperature (1986-2005 to 2081-2100)

RCP8.5

Global mean sea level will continue to rise over the 21st century... and beyond..

.

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+63 cm

Climate change will amplify existing risks and create new risks for natural and human systems.

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Global mean warming

All CO2 emissions since 1750

Global mean warming

All CO2 emissions since 1750

Warming of 0.8 to 2.5°C

1000 billion tons of carbon

Any climate target implies

a limited carbon budget

Budget for the 2°C target:790 bill t C

CO2 emissions until 2014*:−545 bill t C

CO2 emissions in 2014*: 10.1 bill t C

Remaining emissions:245 bill t C

* up

date

d fr

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Limiting climate change would require substantial and

sustained reductions in greenhouse gas emissions which,

together with adaptation, can limit climate change risks.

2°C world

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4.5°C world2°C world

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4.5°C world2°C world

Today we have a choice.